1. Field of the Invention
The present invention relates to a disk assembly and in particular to a disk assembly wherein an annular member is mounted on an outer periphery of a circular plate.
2. Description of the Related Art
As shown in FIGS.8 and 9, a conventional disk assembly 1 includes a a ring gear 2 which is to be regarded as an annular member that is mounted on an outer periphery 3A of a disk plate or circular plate 3. A connection between the ring gear 2 and the disk plate 3 is assured by a welding 4. The disk plate 3 is provided with a plurality of bolt holes 3B for connection to a torque converter, a hole 3D for receiving a crank shaft, a plurality of bolt holes 3E, and a plurality of bolt holes 3F to be used for adjusting the stiffness or rigidity of the disk plate 3.
The foregoing assembly 1 is employed in a torque converter shown in FIG.10 as an assembly of a driving plate 11 and a starting gear 12 as disclosed in Japanese Utility Model Laid-open Print No. 98962 of the 1st year of Heisei Era (1989). It is to be noted that the disk plate 3 and the ring gear 2 correspond to the driving plate 11 and the starting gear 12, respectively.
This assembly serves for the torque transmission between an engine output shaft 13 and a torque converter 14. The gear 12 is set to be brought into engagement with a pinion gear 16 upon engine starting so that the engine is initiated by being transmitted with a force from the starter motor 15 to the output shaft 13 via the gear 12 and the plate 11.
In the foregoing assembly, upon its manufacturing, accuracies are required in the co-axial relationship between the output shaft 13 of the engine and the gear 12, and axial position (the horizontal direction position in FIG.10), which demands careful attention or caution upon the combination of the gear 12 on the plate 11. To meet this demand, the conventional manner has been performed by cutting the outer periphery of the plate 11 on the basis of a reference hole.
However, in such method, the combination of the gear 12 on the plate 11 is established by welding or rivetting, which requires the positioning of the assembly in its axial direction to be performed by using a specific tool with a high degree of skill and the accuracy is not so satisfactory.